scholarly journals DIMENSIONAMENTO, CONSTRUÇÃO E CARACTERÍSTICAS HIDRÁULICAS DE UM INJETOR TIPO VENTURI PARA USO NA QUIMIGAÇÃO

Irriga ◽  
1999 ◽  
Vol 4 (2) ◽  
pp. 43-53 ◽  
Author(s):  
José Crispiniano Feitosa Filho ◽  
José Maria Pinto ◽  
Nivaldo Timóteo de Arruda
Keyword(s):  
High Pressure ◽  
Hydraulic Calculation ◽  
Regression Equations ◽  
Hydraulic Characteristics ◽  
Irrigation Systems ◽  
Head Losses ◽  
Supply Pressure ◽  
Suction Flow ◽  
E Mail ◽  
Made In

DIMENSIONAMENTO, CONSTRUÇÃO E CARACTERÍSTICAS HIDRÁULICAS DE UM INJETOR TIPO VENTURI PARA USO NA QUIMIGAÇÃO   José Crispiniano Feitosa FilhoProfessor do Departamento de Solos e Engenharia Rural do Centro de Ciências Agrárias da UFPB. CEP: 58397-000, Areia-PB. E-Mail: [email protected]é Maria PintoPesquisador da EMBRAPA/CPATSA, CEP. Petrolina-PENivaldo Timóteo de ArrudaProfessor do Departamento de Solos e Engenharia Rural do Centro de Ciências Agrárias da UFPB.   1 RESUMO   O trabalho informa metodologia de construção, dimensionamento e características hidráulicas de um injetor tipo Venturi com potencialidade de uso na Quimigação. Pela resistência do material confeccionado em relação aos injetores tradicionais construídos em polietileno, o injetor metálico pode ser utilizado nos sistemas de irrigação que operam em média ou alta pressão. Estudou-se variáveis como: vazão succionada em função dos diferenciais de pressão, perdas de carga e rendimentos e definiu-se Equações de regressão representativas destas relações. Utilizou-se um injetor com diâmetro nominal na secção de entrada de 75 mm e diâmetro da secção estrangulada de 19,6 mm. Trabalhou-se com pressões de serviço de 10 até 35 mca com incremento de 5 mca. Os resultados mostraram que as vazões succionadas pelo injetor diminuem à medida que o diferencial de pressão, considerando um ponto instalado na secção estrangulada do injetor e outro pós-injetor, aumentaram. As maiores perdas de carga ocorreram nas maiores pressões de serviço, possivelmente, devido ao aumento da vazão motriz no injetor. Os rendimentos diminuíram com o aumento das pressões de serviço e do diferencial de pressão, porém, comportaram-se diferente daqueles apresentados pelas perdas de carga e pelas vazões succionadas. A perda de carga média no injetor foram de 45,11% da pressão de serviço. Os dados das vazões succionadas, das perdas de carga e dos rendimentos analisados por meio de regressão em função dos diferenciais de pressão apresentaram melhores ajustes seguindo modelos de função polinomial quadrática.   UNITERMOS: Quimigação, injetor venturi, dimensionamento hidráulico, irrigação. FEITOSA FILHO, J.C., PINTO, J.M., ARRUDA, N.T. DIMENSIONING, CONSTRUCTION AND HYDRAULIC CHARACTERISTICS OF AN INJECTOR OF VENTURI TYPE FOR USE IN CHEMIGATION   2 ABSTRACT   The work informs construction methodology, measurement and hydraulics characteristic of an injector of Venturi type of with use potentiality in chemigation. For the resistance of the material made in relation to the traditional injectors built in polietileno, the metallic injector can be used in the irrigation systems that operate on the average or high pressure. It was studied variables puch as: suction flow in function of the pressure differentials, load losses and efficiency, and was defined representative regression equations of these relations. The injector was used with nominal diameter in the entrance section of 75 mm and strangled section diameter of 19,6 mm. It was worked with supply pressure of 10 to 35 mca with increment of 5 mca. The results indicated that the suction flow decreases in proportion to the pressure differentials considering a point installed in the strangled section of the injector and other post-injector increased. The major load losses happened possibly in the largest service pressures due to the increase of the motive flow in the injector. The efficiency decreased with the increase of the supply pressures and of the differential pressure even so its behavior were different from those presented by the head losses and for the suction flows. The medium head losses in the injector were of 45,11% of the supply pressure. The data of the suction flow, the load losses and the efficiency analyzed by means of regression in function of the pressure differentials presented better fittings following models of function quadratic polynomial.   KEYWORDS: Chemigation, venturi injector, hydraulic calculation, irrigation. 

Influence of the Accuracy of Determining the Inner Diameter of Pressure Polyethylene Pipes by the Amount of Head Loss by Length

2018 ◽  
Vol 284 ◽  
pp. 1012-1017
Author(s):  
Maria A. Vasilyeva
Keyword(s):  
State Standard ◽  
Head Loss ◽  
Hydraulic Calculation ◽  
Hydraulic Characteristics ◽  
Polyethylene Pipes ◽  
Inner Diameter ◽  
Made In

The article presents the results of the analysis of the requirements of All Union State standard No18599-2001 to the thickness of the walls of pressure polyethylene pipes. An example of hydraulic calculation of a pipeline made of polyethylene PE 100 with a diameter d = 315 mm is considered. It is made in two versions - without taking into account and with allowance for dimensional tolerances stipulated by the requirements of the standard. The influence of the limitations on the thickness of the pipe walls on the values of their internal diameters and hydraulic characteristics is analyzed.

An Analysis of the Control Mechanism Used in Variable-Delivery Hydraulic Pumps

1970 ◽  
Vol 185 (1) ◽  
pp. 63-72 ◽  
Author(s):  
W. L. Green ◽  
T. R. Crossley
Keyword(s):  
High Pressure ◽  
Frequency Response ◽  
Closed Loop ◽  
Control Mechanism ◽  
Relief Valve ◽  
Equal Area ◽  
Design Recommendations ◽  
Supply Pressure ◽  
Servo Actuator ◽  
Made In

Variable-delivery high-pressure hydraulic pumps are usually controlled by a small servo actuator fed from the pump-generated pressure. The actuator consists of a three-way valve and differential-area jack or a four-way valve and equal-area jack. This paper analyses the effect of perturbations of the generated pressure when the pump is part of a system incorporating a relief valve. It is demonstrated that, because the load on the servo jack can be a function of the generated pressure, the ‘closed loop’ formed can be unstable. In particular, the three-way-valve actuator is shown to be sensitive to perturbations in its supply pressure even when the load is independent of pressure. Frequency-response diagrams are presented, the assumptions made in the analysis are clearly discussed, and design recommendations are made in the light of the analytical results.

MODELING THE HYDRAULIC CHARACTERISTICS OF DRAIN VALVE AND BURST FITTING OF AN AIRCRAFT ACCIDENT-RESISTANT FUEL SYSTEM

2020 ◽  
Vol 7 (3) ◽  
pp. 37-44
Author(s):  
KONSTANTIN NAPREENKO ◽  
◽  
ROMAN SAVELEV ◽  
ALEKSEY TROFIMOV ◽  
ANNA LAMTYUGINA ◽  
...  
Keyword(s):  
Mathematical Modeling ◽  
Hydraulic Resistance ◽  
Hydraulic Calculation ◽  
Fuel System ◽  
Hydraulic Characteristics ◽  
System A ◽  
Ansys Cfx ◽  
Calculation Results ◽  
Scale Experiment ◽  
Aircraft Accident

The article discusses methods for determining the hydraulic resistance of units of an accident-resistant fuel system. A detailed description of the need to create such fuel systems for modern helicopters is given. The development of such systems today is impossible without the use of the method of mathematical modeling, which allows to qualitatively solve problems arising in the design process. To obtain accurate research results, it is necessary to have a complete description of all elements and assemblies of the system. Methods for determining the hydraulic characteristics of AFS elements using the drag coefficient, reference literature and CFD codes are considered. As the investigated AFS units, a drain valve and burst fitting were studied in the article. A hydraulic calculation of these AFS elements ware performed, the simulation results are presented in the ANSYS CFX software package. Also as the calculation results of bursting fitting, the pressure distribution fields of full and static pressure, velocity and streamlines are also shown. An experimental setup for validating the results obtained using the mathematical modeling method is considered, as well as a methodology for conducting a full-scale experiment to determine the hydraulic resistance of the unit. Materials have been prepared for inclusion in a one-dimensional mathematical model of an accident-resistant fuel system.

E-Mail made in Science — Sicherheit für den E-Mail Transport mit DANE TLSA

2015 ◽  
Vol 38 (1-2) ◽  
Author(s):  
Helmut Reiser ◽  
Daniel Feuchtinger ◽  
Wolfgang Hommel ◽  
Bernhard Schmidt ◽  
Michael Storz
Keyword(s):  
E Mail ◽  
Made In

Technical regulation for the values of hydraulic parameters of used metal pipes in order to extend the period of their use

2021 ◽  
Vol 18 (3) ◽  
pp. 421-427
Author(s):  
Oleg A. PRODOUS ◽  
◽  
Lev D. TEREKHOV ◽  
Petr P. YAKUBCHIK ◽  
Alexander S. CHERNIKH ◽  
...  
Keyword(s):  
Practical Importance ◽  
Hydraulic Calculation ◽  
Technical Regulation ◽  
Supply Networks ◽  
Steel Pipes ◽  
Head Losses ◽  
Metal Pipes ◽  
Inner Diameter ◽  
Pumping Equipment ◽  
The Given

Objective: To compare the characteristics of hydraulic potential in worn steel pipes with internal deposits subjected to cleaning by mechanical and chemical methods. Methods: Calculated dependencies are used for hydraulic calculation of new metal pipes and pipes with internal deposits. Results: A calculated dependence was obtained to determine the value of the inner diameter of pipes with any thickness of the layer of internal deposits. The concept of an efficient pipeline is introduced and a comparison made of the values of head losses in new pipes and in pipes with internal deposits. A specific practical example is considered. For the given example, compare the values of energy consumption of pumping equipment for two methods of cleaning the inner surface of pipes. Measures are indicated to ensure the efficiency of operation of water supply networks. Practical importance: It is shown that the chemical method of technical regulation of the hydraulic characteristics of new steel pipes provides an extension of the period of their further use.

scholarly journals Ethyl alcohol, a product of high pressure syntheses

1931 ◽  
Vol 131 (818) ◽  
pp. 533-540 ◽  
Keyword(s):  
High Pressure ◽  
Ethyl Alcohol ◽  
Personal Experience ◽  
High Pressures ◽  
Catalytic Reactions ◽  
Chemical Research ◽  
Chemical Research Laboratory ◽  
Pressure Synthesis ◽  
Corroborative Evidence ◽  
Made In

In opening the “discussion on catalytic reactions at high pressures,” one of us (G. T. M.) referred to experiments made in the Chemical Research Laboratory of the Department of Scientific and Industrial Research which had led to the isolation of notable quantities of ethyl alcohol among the condensation products from carbon monoxide and hydrogen interacting at high temperatures and pressures in presence of catalysts. These experiments were first described in March, 1928, and since that date statements have appeared in the scientific press to the effect that ethyl alcohol is a possible exception to the whole sequence of higher alcohols which can be produced by such interactions. Moreover during the above-mentioned discussion Mr. M. P. Appleby, speaking on behalf of the Imperial Chemical Industries, Ltd., Billingham, said “that in our experience we have never succeeded in obtaining, with any catalyst whatsoever, more than a mere trace of ethyl alcohol.” To the latter statement we take no exception whatever. It is a record of personal experience. But we felt that it was desirable to substantiate our earlier experiments by such corroborative evidence as would leave no doubt that ethyl alcohol is a product of high pressure synthesis.

The influence of pressure on the infrared spectra of hydrogen bonded solids. II. Bihalide salts

1976 ◽  
Vol 29 (3) ◽  
pp. 479 ◽  
Author(s):  
SD Hamann ◽  
M Linton
Keyword(s):  
Phase Transition ◽  
High Pressure ◽  
Hydrogen Bonds ◽  
High Pressure Phase Transition ◽  
Infrared Measurements ◽  
Normal Hydrogen ◽  
Combination Bands ◽  
Pressure Phase ◽  
Made In ◽  
Hydrogen Bonded

Infrared measurements have been made of the influence of pressures between 0 and 40 kbar on the asymmetrical stretching frequencies v3 and bending frequencies v2 of the hydrogen-bonded ions FHF- and ClHCl- in the solid salts NaHF2, KHF2, NH4HF2, (CH3)4NHCl2 and (C2H5)4NHCl2 at 25�C. The behaviour of the symmetrical stretching frequency v1 for FHF- in KHF2 has been deduced indirectly from the shifts of combination bands. Contrary to the behaviour of compounds with weaker, 'normal', hydrogen bonds, the v3 bands shift to higher frequencies and the v2 bands shift to lower frequencies with increasing pressure. The vl band of KHF2 shifts to higher frequencies. These trends are all in agreement with predictions made in Part I for a simple model of hydrogen bonds. A new high-pressure phase transition has been found to occur in NaHF2 at about 40 kbar.

New Strong Inhibitory Polyamine Drilling Fluid System Research in Yubei Area

2013 ◽  
Vol 807-809 ◽  
pp. 2519-2522
Author(s):  
Wan Long Huang ◽  
Yi Shan Lou ◽  
Liang Zhu ◽  
Zhong Hui Li
Keyword(s):  
Water Pollution ◽  
High Pressure ◽  
Salt Water ◽  
Drilling Fluid ◽  
Well Bore ◽  
System Research ◽  
Fluid System ◽  
Temperature Resistance ◽  
Evaluation Test ◽  
Made In

Yubei area exist thick mud shale, mudstone, gypsum mudstone and high pressure brine formation. In the course of drilling, the problems are most conspicuous which include well bore instability, bit balling and so on. In allusion to complex formation and complex accident, the polyamine form strong inhibitory polyamine collapse prevention drilling fluid on the basis of KCl-polysulfonate drilling fluid system was used in Yubei area. After the analysis on the mechanism of the strong inhibitory polyamine polymer drilling fluid system, the polyamine performance evaluation test made in laboratory shows that the drilling fluid system has good rheological property, high temperature resistance, clay and salt water pollution resistance. This drilling fluid system cooperate with KCl improve the ability of inhibition of drilling fluid, meet the requirements of stabilize borehole wall, which carried on the field test in YB A well has obtained good application effect.

scholarly journals The effects of irrigation modernization on the cost recovery of water in the Valencia Region (Spain)

2013 ◽  
Vol 14 (3) ◽  
pp. 414-420 ◽  
Author(s):  
Marta García-Mollá ◽  
Mar Ortega-Reig ◽  
Carles Sanchis-Ibor ◽  
Llorenç Avellà-Reus
Keyword(s):  
Cost Recovery ◽  
Irrigation Systems ◽  
Structural Water ◽  
Regional Administration ◽  
Water Users ◽  
Recovery Percentage ◽  
The One ◽  
The Cost ◽  
Made In ◽  
Main Strategy

The modernization of the irrigation systems has been the main strategy followed by the regional administration of the Valencia Region to cope with the structural water deficit of the region, which has been particularly severe during the last three decades. These policies have been oriented to the substitution of gravity irrigation systems for drip technology. The technological change has involved an important investment effort, developed by different public administrations and also the farmers and water users' associations (WUAs). This transformation, has also involved a change in the structure of costs of the WUAs. This paper analyzes the changes in costs and tariffs of irrigation after the important investments made in the modernization of irrigation. The effects of subsidies on the percentage of the cost recovery in the services of water for irrigation are also considered. All of them have developed modernization projects in the recent years. It can be concluded that conflict between two objectives proposed by the Water Framework Directive may exist. On the one hand, significant reductions of water supply are observed; meanwhile, on the other hand, the cost recovery percentage diminishes significantly.

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